While Burch sells a variety of items, it's obvious that her signature ballet flat catapulted her to icon status. Her company is valued at $3.5 billion and investors are speculating that the company could go public soon.

Before Burch, ballet flats were a utilitarian item that most women wore on their way to work. They came in plain colors and were quickly put away in favor of heels. While many brands offered them, whether they came from Payless or Nordstrom was virtually indistinguishable.

But Burch did something on a large scale that no retailer had before.

She created ballet flats that symbolized status and style by adding medallions with a logo to the slipper. Thus, women weren't just wearing ballet flats — they were making a chic fashion statement.

Burch's ballet flats were also aspirational in that women felt they needed them to make a statement. While ballet flats were once boring commuter tools, Burch turned them into something that excited women and made them feel special.

Focusing on the ballet flat also allowed Burch to differentiate herself in a tough fashion market.

Coach had the handbag market on lockdown, while Michael Kors was known for watches. By charting unknown territory, Burch was able to offer something that her competitors didn't have and jump-start her business.